以锌镍合金电镀替代化学镀镍作为中间层的铝合金无氰镀镉工艺  

Process for cyanide-free cadmium electroplating on aluminum alloy with electroplated zinc–nickel alloy coating instead of electrolessly plated nickel coating as an intermediate layer

作　　者：郭崇武[1] GUO Chong-wu(Guangzhou Ultra Union Chemicals Ltd., Guangzhou 510460, China)

机构地区：[1]广州超邦化工有限公司,广东广州510460

出　　处：《电镀与涂饰》2018年第5期217-219,共3页Electroplating & Finishing

摘　　要：在铝合金表面依次制备浸锌层、锌镍合金预镀层、氯化钾无氰镀镉层和铬酸盐低铬钝化层。锌镍合金预镀采用碱性或酸性工艺皆可。经处理的铝合金在热震试验后没有出现镀层起泡和脱落,在耐中性盐雾试验中耐白锈的时间长达2 520 h,可见镀层的结合力与耐蚀性良好。这种镀层结构克服了现行以化学镀镍作为中间层时镀层容易起泡的缺陷。Zinc immersion,Zn-Ni alloy pre-plating,cyanide-free potassium chloride cadmium coating,and low chromium chromate passivation layer were successively carried out on the surface of aluminum alloy.The Zn-Ni alloy coating is made in either an alkaline bath or an acidic bath.The coatings prepared on aluminum alloys have good adhesion strength and corrosion resistance in that no blistering and fall-off occurred after thermal shock test,and no white rust was formed after a2520-hour neutral salt spray test.The coating structure overcomes the blistering problem often occurred for that commonly used with electrolessly plated nickel coating as an intermediate layer.

关 键 词：铝合金 氯化钾无氰镀镉 锌镍合金预镀 耐蚀性 结合力 

分 类 号：TQ153.1[化学工程—电化学工业]